1 // SPDX-License-Identifier: GPL-2.0
2
3 #include <linux/kernel.h>
4 #include <linux/kgdb.h>
5 #include <linux/printk.h>
6 #include <linux/sched/debug.h>
7 #include <linux/delay.h>
8 #include <linux/reboot.h>
9
10 #include <asm/pdc.h>
11 #include <asm/pdc_chassis.h>
12
13 unsigned int __aligned(16) toc_lock = 1;
14
toc20_to_pt_regs(struct pt_regs * regs,struct pdc_toc_pim_20 * toc)15 static void toc20_to_pt_regs(struct pt_regs *regs, struct pdc_toc_pim_20 *toc)
16 {
17 int i;
18
19 regs->gr[0] = (unsigned long)toc->cr[22];
20
21 for (i = 1; i < 32; i++)
22 regs->gr[i] = (unsigned long)toc->gr[i];
23
24 for (i = 0; i < 8; i++)
25 regs->sr[i] = (unsigned long)toc->sr[i];
26
27 regs->iasq[0] = (unsigned long)toc->cr[17];
28 regs->iasq[1] = (unsigned long)toc->iasq_back;
29 regs->iaoq[0] = (unsigned long)toc->cr[18];
30 regs->iaoq[1] = (unsigned long)toc->iaoq_back;
31
32 regs->sar = (unsigned long)toc->cr[11];
33 regs->iir = (unsigned long)toc->cr[19];
34 regs->isr = (unsigned long)toc->cr[20];
35 regs->ior = (unsigned long)toc->cr[21];
36 }
37
toc11_to_pt_regs(struct pt_regs * regs,struct pdc_toc_pim_11 * toc)38 static void toc11_to_pt_regs(struct pt_regs *regs, struct pdc_toc_pim_11 *toc)
39 {
40 int i;
41
42 regs->gr[0] = toc->cr[22];
43
44 for (i = 1; i < 32; i++)
45 regs->gr[i] = toc->gr[i];
46
47 for (i = 0; i < 8; i++)
48 regs->sr[i] = toc->sr[i];
49
50 regs->iasq[0] = toc->cr[17];
51 regs->iasq[1] = toc->iasq_back;
52 regs->iaoq[0] = toc->cr[18];
53 regs->iaoq[1] = toc->iaoq_back;
54
55 regs->sar = toc->cr[11];
56 regs->iir = toc->cr[19];
57 regs->isr = toc->cr[20];
58 regs->ior = toc->cr[21];
59 }
60
toc_intr(struct pt_regs * regs)61 void notrace __noreturn __cold toc_intr(struct pt_regs *regs)
62 {
63 struct pdc_toc_pim_20 pim_data20;
64 struct pdc_toc_pim_11 pim_data11;
65
66 nmi_enter();
67
68 if (boot_cpu_data.cpu_type >= pcxu) {
69 if (pdc_pim_toc20(&pim_data20))
70 panic("Failed to get PIM data");
71 toc20_to_pt_regs(regs, &pim_data20);
72 } else {
73 if (pdc_pim_toc11(&pim_data11))
74 panic("Failed to get PIM data");
75 toc11_to_pt_regs(regs, &pim_data11);
76 }
77
78 #ifdef CONFIG_KGDB
79 if (atomic_read(&kgdb_active) != -1)
80 kgdb_nmicallback(raw_smp_processor_id(), regs);
81 kgdb_handle_exception(9, SIGTRAP, 0, regs);
82 #endif
83 show_regs(regs);
84
85 /* give other CPUs time to show their backtrace */
86 mdelay(2000);
87 machine_restart("TOC");
88
89 /* should never reach this */
90 panic("TOC");
91 }
92
setup_toc(void)93 static __init int setup_toc(void)
94 {
95 unsigned int csum = 0;
96 unsigned long toc_code = (unsigned long)dereference_function_descriptor(toc_handler);
97 int i;
98
99 PAGE0->vec_toc = __pa(toc_code) & 0xffffffff;
100 #ifdef CONFIG_64BIT
101 PAGE0->vec_toc_hi = __pa(toc_code) >> 32;
102 #endif
103 PAGE0->vec_toclen = toc_handler_size;
104
105 for (i = 0; i < toc_handler_size/4; i++)
106 csum += ((u32 *)toc_code)[i];
107 toc_handler_csum = -csum;
108 pr_info("TOC handler registered\n");
109 return 0;
110 }
111 early_initcall(setup_toc);
112